US 3820102 A
Description (OCR text may contain errors)
United States Patent 1191 Schubert [5 1 PREMISES ENTRY AND EXIT SIGNALING- SYSTEM  inventor: Howard C. Schubert, Leonia, NJ.
 Assignee: Aerolite Electronics Corp., Union City, NJ.
221 Filed: July 24, 1972 21 App1.No.:274,806
Morgan 425/l46 v 1451 June'25, 1974 Primary ExaminerJohn W. Caldwell Assistant Examiner- Glen R. Swann, Ill
[ ABSTRACT The system includes a signaling circuit adapted to provide a signal when the protected premises have been entered or left by authorized personnel and a gate means controlling the operation of the signaling circuit. The gate is operated by a-second circuit which includes a warning light, a master multi-position switch located inside the premises, a normally-open switch, and a normally-closed outside switch located outside the premises. ,The connections are such that the master switch is used to operate the system when authorized personnel enter the premises, but the combined action of the masterv switch and outside switch are required when authorized personnel leave the premises. Tampering with the outside switch is of no effect once the system has been set.
PATENIEBJHEZS m4: 1 SHEET 5 UF 6 1270 F F g. 6 80 Audi Micro hone Amp. TO 5Q 12 0 13001 4 5L 1290 goo 6O 90 (I, qoqcu 1e Module 42 50 1330 j woof 410 'IOO 1310A 13105 To 40 1320 Audio 1340 Amp 1350 v Speaker PREMISES ENTRY AND EXIT SIGNALING I SYSTEM CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of application Ser. No. 879,258, filed Nov. 24, 1969 and now abandoned BACKGROUND OF THE INVENTION SUMMARY OF THE INVENTION The present invention includes a signaling circuit for generating a signal to show authorized entry and exit from the protected premises and an interior switch for providing first step energization of the system, and an external control means which completely energizes the system but has no effect on the system if it is tampered with.
DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic representation of a system em bodying the invention and a portion of a burglar alarm system with which it can be used;
FIG. 2 is a schematic representation of another portion of said burglar alarm system;
FIG. 3 is a schematic representation of a modification of a portion of the system of FIG. 1;
FIG. 4 is a schematic representation of another modification of a portion of the system of FIG. 1;
F IG. 5 is a schematic representation of still another modification of a portion of the system of FIG. 1;
FIG. 6 is a schematic representation of another modification of a portion of the system of FIG. 1;
FIG. 7 is a schematic representation of another modification of a portion of the system of FIG. 1;and
FIG. 8 is a schematic representation of another modification of a portion of the system of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS ter control switch 42 which is preferably key-operated and has a key-operated rotary contactor 52 and a plurality of operating contacts or positions including an OFF contact 62, a battery test contact 72, a system test contact 82, a door set contact 92, and an ON contact 102. The switch 42 and its associated circuit is preferably mounted in a suitable box or housing (not shown) at a convenient location inside the premises with which the invention is associated and which are to be protected.
The system 12 includes a primary power source, for example, a first battery 112, which has its negative terminal connected by lead 122 to the movable arm 132 of a C-type reed switch 142. The movable arm 132 of switch 142 is normally closed in contact with terminal 144 which is connected by a lead 152 to the rotor 52 of switch 42. Thus, negative battery potential is normally always applied to the switch rotor 52.
The system test contact 82 and the ON contact 102 of the switch 42 are connected together by lead 162 to an associated burglar alarm system of any suitable type. One such burglar alarm system is disclosed and claimed in [1.8. Pat. No. 3,603,947. This system, including module 20 (FIG. 1) and modules and 420 (FIG. 2), is also shown and described herein to illustrate the invention. Module 22 is coupled to on-premises alarm condition sensing module 20 by lead 162 which extends from contacts 102 and 82 of switch 42 to negative reference bus 50 of module 20. Module 20 and the other portions of the burglar alarm system are described in detail below.
Referring again to module 22 of the system 12, the positive terminal of battery 112 is coupled by lead 172 to the positive reference bus 182 .of signaling module 32 and by lead 202 to a normally-closed push button door switch 212 which is mounted at an accessible location near a door outside the premises. This is represented by a dash line enclosure. Several such push button door switches 212 might be provided at several doors and connected in series to permit entry or exit and operation thereof at more than one door. Push button door switch 212 is connected by leads 221 and 222 to one end 231 of the inductor winding 232 of reed switch 142. The other end 242 of the inductor 232 is connected by bus 252 to the normally-open contact 262 of reed switch 142 and thence by but 272 to doorset contact 92 of key-operated switch 42. End 242 of winding 232 is also coupled by lead 282 to signaling circuit module 32.
A warning light indicator 292 is connected in parallel with the inductor winding 232 of reed switch 142 between leads 222 and 282 and is arranged to light only when reed switch 142 is energized, as described below. One such warning light is provided for each push button switch 212.
The signal module 32 includes common bus 182 and common bus 302. Lead 282 from end 242 of the inductor 232 is connected through parallel connected resistor R1 and capacitor C1 to common bus 182, and through resistor R2 to the base of transistor T1. The emitter of transistor T1 is connected to bus 182, and its collector is connected through resistor R3 to but 302. bus collector of transistor T1 is also connected through capacitor C2 to lead 364 which is connected through capacitor C3 and resistor R4 to bus 182 and through diode D1. oriented as shown for a purpose to be described, to bus 302. The junction 394 of resistor R4 and capacitor C3 is also connected to the base of transistor T2, the emitter of which is connected to bus 182, and the collector of which is connected through resistor R5 to bus 302.
The collector of transistor T2 is also connected through a diode D2, oriented as shown, both through a resistor R6 to bus 302 and to the gate of the threeelectrode controlled rectifier, SCRl, the anode of which is connected through resistor R7 to bus 182, and the cathode of which is connected to bus 302. The anode of rectifier SCRl is also connected by lead 454 through capacitor C4 and resistor R8 to bus 182 and through resistor R9 to one base of unijunction transistor UJl. The junction of capacitor C4 and resistor R8 is connected to the emitter of U] 1, the other base of UJl is connected through resistor R10 to bus 182, and the aforementioned one base of UM is connected by capacitor C5 to bus 302.
Lead 454 from the anode of SCR] is also connected through resistor R11 to the base of transistor T3, the emitter of which is connected to bus 182, and the collector of which is connected to a lead 524 which itself is connected (1 through resistor R12 to bus 302, and (2) through resistor R13 and capacitor C6 to bus 302 and through resistor R14 to one base of U12. The other base of UJ2 is connected to bus 302, and its emitter is connected both to the junction of resistor R13 and capacitor C6,and by lead 574 to the base of transistor T4, the emitter of which is connected to bus 302, and the collector of which is connected to the base of transistor T5. The emitter of transistor T5 is connected to bus 182, and the collector is connected through the inductor 602 of a normally closed A-type reed switch 611 having normally-closed contacts 612 and 614, connected to terminals 341 and 340, respectively, which are inserted in one of two telephone lines, e.g., line 400 (FIG. 2) to be discussed further below. Thus, transistor T5 is coupled to remote signaling devices at a monitoring station, the devices including a normal signal light 580, a trouble signal light 560, and alarm 600. Other signaling devices may be provided, if desired.
The alarm system described in the above-mentioned patent includinj modules (FIG. 1) and 110 and 420 (FIG. 2) and its mode of operation will now be described.
The alarm system module 20 (FIG. I) has an alarm indicator including a three-electrode semiconductor gate or switching device 60 known as an SCR connected in series with load resistor 70 between buses 40 and 50 with an alarm bell or horn or the like represented by block 80 connected across resistor 70. The gate of SCR 60 is connected through a resistor 82 to bus 50 and to negative potential supplied by battery 150. Battery 112 provides positive potential to bus 40 through lead 192. SCR 60 is normally held off by the applied potentials. The anode of SCR 60 is also coupled through diode 90, lead 100, and rotor 52 and ON contact 102' of switch 42' and lead 107 to module 110 (FIG. 2), a polarity-reversing circuit, to be described. Switch 42' is ganged to switch 42 and has ON and OFF contacts 62' and 102' which operate with contacts 62 and 102 of switch 42. Switch 42' is used to disconnect module 110 from system 12 when switch rotor 52 passes through contacts 72, 82, and 92.
A first alarm-sensing arrangement in module 20 (FIG. 1) includes a semiconductor switch 120, preferably a GE. 4987 switch, having its anode A connected through a resistor 130 to the bus 40 and thus to positive potential, and its gate G connected through a normally closed switch 140 to the positive terminal of DC power source 150. The cathode K of switch 120 is connected by lead 160 to the gate G of SCR 60. Power source 150 normally holds switch 120 non-conducting, and switch 140 represents a mechanical or electronic alarm-sensor switch or any othersensing mechanism which, when opened, upsets the bias arrangement and permits switch to conduct current from anode to cathode and to the gate of SCR 60 which also then conducts, energizes alarm 80, and provides an output current on lead 100 from diode 90. Device represents one or more alarm-sensing devices which may be connected in series or parallel as desired, in the windows, doors, or the like of the premises being protected.
A second similar alarm-sensing arrangement in module 20 includes a nomially open switch which, like switch 140, represents an alarm sensor connected in series with a resistor between buses 40 and 50. Again, a plurality of similar alarm sensors might be connected in parallel. This sensing arrangement also includes a second similar unilateral switch having its anode A connected through a resistor 200 to bus 40 and its gate G connected to the lead 210 between resistor 180 and switch 170. The cathode electrode K of switch 190 is connected both through a variable resistor 220 and capacitor 230 to bus 50 and through a second resistor 240 to one base A of a unijunction transistor 250. The junction of the variable resistor 220 and the capacitor 230 is connected to the trigger or emitter T of the unijunction transistor 250, and the other base K of the unijunction transistor is connected to the gate of the SCR 60. Resistor 220 and capacitor 230 comprise an adjustable timing circuit for controlling the charging time of capacitor 230 and the turn-on time of unijunction transistor 250. This time-delay mechanism permits an authorized entrant to trip sensor 170 and then reset it before alarm 80 is set off.
Sensors 140 and 170 are shown as normally closed and normally open, respectively, to indicate that mod ule 20 can accommodate alarm sensors of different types in its two sensing circuit loops.
In the polarity-reversing module 110 (FIG. 2), the lead 107 from module 20 is connected to the gate G of a unilateral switch 260, the anode A of which is connected through a resistor 270 to bus 40. Switch 260 is normally held non-conductive. The gate G is also connected through a resistor 280 to the bus 40. The cathode K of the switch 260 is connected to the base of an NPN transistor 290, the emitter of which is connected to the bus 292, and the collector of which is connected to the base of a PNP transistor 300. The PNP transistor 300 has its collector connected to the lead 292 and its emitter connected by lead 310 to the base electrodes of two PNP transistors 320 and 330. The emitter of the transistor 320 is connected to an output terminal 340 and through a load resistor 350 and a lead 360 tothe positive terminal of a DC. power source 370, the negative terminal of which is connected to the bus 292. The transistor 320 also has its collector electrode connected to the bus 292. The transistor 330 has its emitter electrode connected to the lead 360, and its collector electrode connected both to an output terminal 380 and through a load resistor 390 to the bus 292.
Module 110 operates as follows. With module 20 (FIG. 1) quiescent and no alarm condition present, no signal is conducted through diode 90 to module 110, and this module is quiescent. In the quiescent state of module 110, switch 260 and all transistors are nonconducting and terminal 340 connected to (telephone) line 400 carries positive potential, and terminal380 connected to (telephone) line 410 carries negative potential. When an alarm condition in module 20 provides current flow on lead 107, switch 260 conducts and transistors 290 and 300 turn on, and this causes transistors 320 and 330 to turn on. Now, the emitter of transistor 320 assumes a negative potential, as does terminal 340 and line 400, and the collector of transistor 330 assumes a positive potential, as does terminal 380 and line 410. Thus, it can be seen that the normal polarity of terminals 340 and 380 and lines 400 and 410 are reversed during an alarm-indicating condition of the system.
Lines 400 and 410 are input leads to module 420 and are coupled to terminals 340 and 380 at the output of module 110. Lines 400 and 410 represent telephone lines or the like to a remote location, for example, a police station, firehouse, or the like, at which module 420 may be remotely located.
Line 400 is coupled through a diode 422 oriented as shown to line 430. Line 410 is coupled through an oppositely oriented diode 440 as shown to line 450. Line 400 is also coupled through lead 460 and diode 470 oriented oppositely to diode 422 to line 430, and line 410 is also connected through lead 490m a diode 500 oriented oppositely to diode 440 to line 510. Lines 450 and 480 are connected together by a lead 520, and line 430 is coupled to the base electrodes of two NPN transistors 530 and 540. Line 510 is coupled to the base electrode of another NPN transistor 550.
The module 420 includes a first trouble light 560 in series with an SCR 570 and lead 630, a normal light 580 in series with an SCR 590 and lead 630, and an alarm light or signal600 of any suitable type in series with an SCR 610 and lead 630. The cathodes of the SCRs 570, 590, and 610 are connected together by lead 620, and lead 630 is connected to one side of an AC. power source 640. The gate electrodes of the SCRs 570, 590, and 610 are also connected through resistors 650 to a common bus 660 which represents reference potential and is connected by lead 980 to the other side of power source 640.
The first-described portions of module 420 and the alarm or normal indicators are interconnected as follows. The collector of transistor 530 is connected by lead 700 through resistor 710 to the gate of SCR .570 to trouble indicator 560 and through resistor 720 and lead 730 to bus 740. The emitters of transistors 530 and 540 are connected through resistors 750 to lead 451 which is connected to reference bus 660. The emitter of transistor 540 is connected by lead 760 and resistor 770 to the gate of SCR 590 to the normal indicator 580, and the collector of transistor 540 is connected through resistor 780 to bus 730 and bus 740 to the power supply 640.
Line 400 is connected through lead 460, diode 470, lead 480, resistor 790, lead 800 and resistor 810 to the gate of SCR 610 of alarm indicator 600. The emitter of transistor 550 is connected to lead 800 and resistor 810 to the gate of SCR 610, and its collector is connected through resistor 820 and lead 740 to the power "supply 640.
The power supply 640 for the system 10 includes the usual 110 volt, cycle AC. power source 900 coupled to a transformer having primary and secondary windings 910 and 920, respectively. The secondary winding of the transformer has one end connected through a lead 930 to lead 630 which is connected to one side of each of the signal devices 560, 580, and 600. This connection provides alternating current across these devices between bus 630 and bus 660. This end of the secondary winding of the transformer is also connected through a diode 950 and lead 960 to the lead 740 to provide half-wave rectified DC. on lead 740 and'thus to lead 730. The other end of the secon dary winding of the transformer is connected by leads 930 and 980 to the reference bus 660. A capacitor 990 is connected between leads 960 and 980. This capacitor acts as a filter and phase shifter and provides the signal for operating the various lights and alarms as described below.
An auxiliary alarm circuit is also provided including an SCR 1000 having its cathode connected to the lead or bus 980 and its anode connected through a load resistor 1010, a lead 1012, and a switch 1020 to the lead 960. A suitable alarm 1030 is connected across the load resistor 1010. The gate of the SCR 1000 is connected both through a resistor 1040 to the reference bus 980 and to lead 890 to capacitor 880.
Referring to circuit module 420, as mentioned, when the system is normal, that is, no alarm condition exists in module 20, linev 400 is plus and line 410 is minus. With line 400 plus, positive voltage is coupled through diode 422 to turn on both NPN transistors 530 and 540. With transistor 530 turned on, its collector is at ground potential so that the signal voltage which is applied to bus 740 from the capacitor 990 in the power supply is fed to ground and SCR 570 is not turned on and trouble light 560 is not turned on. With NPN transistor 540 on, a path is provided through its emitter-collector path for the signal on bus 740, and this is applied to the gate of SCR 590 which opens and passes a current which turns on the normal light 580.
If potential is removed from lines 400 and 410 for any reason, either due to opening of a line or shorting of the lines, then the transistors 530 and 540 remain off and trouble light 560 is turned on by the signal voltage on lines 740 and 730 passing through resistors 720 and 710 to the gate of SCR 570 which is rendered conductive.
When the potentials on lines 400 and 410 are reversed indicating an alarm condition, diodes 422 and 440 are blocked, transistors 530 and 540 are off and signal voltage is coupled from the power supply through lines 740 and 730 through resistor 720 to the gate of SCR 570 which conducts and trouble light 560 goes on. Also, diodes 470 and 500 open, and the positive potential on line 410 now operates through diode 500, to turn on transistor 550. The emittercollector path of transistor 550 passes signal voltage on line 740 through lead 800 and resistor 810 to the gate of SCR 610, which thereby conducts and turns on the alarm600. a
In addition, plus voltage applied to diode 500 is applied to the anode of SCR 860, and current flow through resistor 830 charges capacitor 840 which, when charged, acts on the gate of SCR 860 to turn on SCR 860 and send a pulse through capacitor 880 to turn on remote SCR 1000 and thus activate remote alarm 1030 shown in the power supply circuit. This arrangement using capacitor 840 prevents spurious noise pulses from turning on SCR 860 since such pulses are fedto ground through resistor 900 and do not charge the capacitor. Switch 1020 can be used to tie-activate or turn off alarm 1030, if this is desired, without affecting the other alarms in the system.
Reference is now made to the operation of modules 22 and 32 of system 12. System 12 is intended to be operated when personnel leave, say a business bulding, at the normal time at the end of a work day and when they enter the building at the normal time at the beginning of the work day. When the system is operated at these two times, signaling circuit 32 operates to flash warning lights off and on at a remote location such as a police station. The police station personnel are alerted to watch for the systems operation at these times, and, as a result, they are automatically alerted if the timed operations do not occur. Of course, it will be clear that the system of the invention, and particularly signal module 32, could be used in some other fashion other than to operate remote flashing lights. In any case, the arming of the system, to be described, would be the same however module 32 is used.
Referring now to system 12, operation thereof is as follows. Consider the system at some time during the day and before the end-of-the-day setting. At this time,
. terminal by way of bus 172. Any previous charge on capacitor Cl is, or has been, discharged by resistor R1.
When negative battery potential is absent from the R1*C1R2 combination, transistor T1 is nonconducting. Transistor T1 is also held off by positive hold-off battery potential fed over resistors Rl-R2 to the base of transistor T1. Capacitor C2 is discharged by resistor R3 and positive pulse clipper diode D1, and coupling capacitor C3 is charged over resistor R4, and this provides positive bias on the base of transistor T2, thus assuring tha transistor T2 is held off when switch 42 is off.
With the system in the OFF condition, rectifier SCRl is non-conducting, so that capacitor C4 cannot charge,
unijunction transistor UJl cannot conduct, and t'ransistor T3 cannot conduct. Because transistor T3 is nonconducting, unijunction transistor UJ2 cannot conduct and capacitor C6 cannot charge. Transistors T4 and T5 are also non-conducting, with transistor T4 being held off by the negative bias applied to its base over resistors R12 and R13.
Since transistor T5 is non-conducting, reed switch 611 is not energized, is closed, and thus is connected in series with battery 370 and transmission line 400 to the remote signal lights in module 420. Thus, battery potential is supplied to the remote monitoring station so that the normal light 580 in ON.
At the end of the work day, the system is set as follows. Authorized personnel, on preparing to leave the premises, turn the rotor 52 of switch 42 from the OFF contact 62 to the ON contact 102. During this movement of the rotor 52, it momentarily touches contact 92, whereby a path is completed from the negative terminal of battery 112 through switch arm 132, contact 144, lead 152, contact 92, and leads 272 and 252 to the inductor 232 of switch 142 and through the other circuit elements shown, including switch 212, to the positive terminal of the battery 112. Current now flows in the inductor coil 232 and through the path including warning light 292, and the light goes on. Current flow in coil 232 attracts the arm 132 of the reed switch 142 from the contact 144 to the contact 262. The negative battery potential is thus maintained on the inductor even though rotor 52 is on the ON contact 102, and the arm 132 is locked into contact with switch terminal 262. Thus, the negative terminal of battery 112 is removed from bus 152 and from bus 162 to the alarm system which is disabled until the entire system has been set. Because the door lamp or lamps 292 are in parallel with the inductor 232 of reed switch 142, they remain lit as an indicator and reminder to the person locking the premises that the alarm system is still not fully activated and no remote indication has been given by signal circuit 32.
Negative potential on bus 252 and bus 282 completes a circuit through which capacitor C1 charges and turns on transistor T1 by supplying negative potential to the base of transistor T1 over resistor R2. Current flow through transistor T1 charges capacitorsCZ and C3. However, transistor T2 does not conduct because its base is positively biased and coupling capacitor C3 is charged. It is to be noted that any small noise pulse which might occur at the junction of capacitors C2 and C3 is clipped by diode D1. Because transistor T2 is non-conductive, the rest of circuit 32 following it remains inoperative.
On leaving the premises, the authorized personnel depresses and thus opens the normally closed push button door switch 212 which is outside the premises. This momentarily disconnects the battery positive potential from buses 221 and 222 and interrupts current flow in the inductor 232 of reed switch 142. This action simultaneously extinguishes the reminder door lamp 292. Reed switch 142 returns to the normally closed position in which arm 132 contacts terminal 144, and negative battery potential is supplied over arm 132, bus 152, switch rotor 52 and bus 162 to the burglar alarm system which is now activated and ready for normal operation.
Once the push-button door switch 212 is depressed and the door lamp 292 is extinguished, they are disconnected from the battery circuit because switch 42 in its housing inside the protected premises is in the ON position and switch arm 132 is in contact with terminal 144. Negative battery potential is now also removed from buses 252, 272 and 282, and, as a result, capacitor C1 gradually discharges over resistor R1, and transistor T1 slowly returns to a non-conducting state over the time period during which capacitor C1 discharges.
Capacitors C2 and C3'now discharge over resistor R3 because positive potential is reduced at the collector of i transistor T1. During the discharge period of capacitors C1, C2, and C3, transistor T2 becomes conductive and, after ,a period of time, returns to a non-conductive state. During this conductive period of transistor T2, a large positive pulse is generated from its emitter to its collector that passes through diode D2 and turns on the controlled rectifier SCRl. Rectifier SCRl now supplies a negative potential to capacitor C4 and a negative bias to the base of transistor T3 which is turned on, and capacitor C4 charges slowly over resistor R8.
Because transistor T3 is now conductive, capacitor C6 charges quickly, and the sawtooth waveshape of the charging potential of capacitor C6 turns on transistors T4 and T5. Transistor T5 supplies current to the inductor of reed switch 611 through resistor R12. This opens the contact of the normally closed reed switch and removes the battery 370' from the transmission line 400. As a result, at the remote monitor station, the normal lamp 580 turns off and the trouble lamp 560 turns on.
When capacitor C6 is fully charged, it turns on and discharges through transistor UJ2, and this turns off transistors T4 and T5, as a result of which reed switch 611 closes. Now the remote trouble lamp 560 turns off, and the normal lamp 580 turns on. At this time, capacitor C4 is still charging through conductive rectifier SCR] and transistor T3 is conductive, and the cycle of switching of lights 560 and 580 is repeated by operation of fast charging capacitor C6 and transistor T4 and T5 to switch the remote normal light off and the trouble light on. When C6 is fully charged, it again turns on and discharges through transistor U12 and turns off transistors T4 and T5 and closes switch 611 to turn off the trouble light and turn on the normal light. This cycle and the flashing of the normal and trouble lights continues until capacitor C4 is fully charged.
When capacitor C4 is fully charged, it turns on and is discharged by transistor UJl. The momentary conduction of transistor U11 supplies a pulse to the anode of rectifier SCRl which is turned off. Reed switch 611 returns to the normally closed position to provide continuous battery power to the remote station so that the normal indicator lamp remains on. This light cycling operation represents a normal evening happening to police at the remote location. It tells them that the premises are empty and the alarm system is set at the correct time of day.
Typically, capacitor C4 is designed to require a long charging period, say one minute, and capacitor C6 is designed to charge quickly, in about one second. Consequently, the telephone line reed switch 611 opens and closes, and the lights flash about sixty times during the charging period .of capacitor C4.
In the morning, when authorized personnel return to the premises, switch 42 inside the building is turned back to the OFF position 62, and, as its rotor 52 is turned, it again contacts the door set position 92, operates switch 142 to close contact 262 and to charge capacitors C1, C2, C3, as described above. Transistor T1 is on, but transistor T2 and the rest of module 32 is disabled. When rotor 52 goes to OFF contact 60, it removes negative potential from the signal circuit 32, and capacitors C1, C2, C3 discharge and cause the light flashing cycle to operate as above and thus advise the remote police station that the premises have been entered in normal fashion. Since the turning of rotor 52 to the OFF contact 62 removes negative battery potential from the circuit and causes the flashing cycle to be executed, operation of the push button 212 is not required.
The present invention provides an efficient system for use in conjunction with a burglar alarm system for indicating, to police or other authorities, authorized entry into and exit from the protected premises. One of the important advantages of the invention is that the system can be operated inside the premises on entering and outside the premises on leaving. However, the
mechanism operated outside the premises is not connected'to the primary burglar alarm system so that, even if it is tampered with, the alarm system is still operable in normal fashion.
It is to be noted that the system described can be used to provide a signal other than flashing lights and it may be used in conjunction with other types of burglar alarm systems.
The system of the invention also includes a returnsignal indicator apparatus for the purpose of having the remote station positively indicate that it has received a status signal from the protected premises. This apparatus, including a portion of the system described above, is illustrated in FIG. 3 and includes, in one suitable arrangement, a switching device 1100, for example. a PNP transistor having its emitter connected to bus 40 and its collector connected through a lamp 1110 to the other bus 50. The base of the transistor 1100 is connected through a suitable resistive path 1120 to the positive terminal of battery 370. The apparatus also includes a normally open switch 1130 at the remote receiving station which is connected across leads or telephone lines 400 and 410.
In operation of this apparatus, after the system has been set and a signal has been transmitted to the remote station by the flasher circuit 32, an operator there closes switch 1130 to short circuit leads 400 and 410, and this, in turn, causes transistor 1100 to conduct and turn on lamp 1110.- When the switch 1130 is opened, the lamp 1110 turns off. A person on the premises thus knows that the system has operated properly.
Still another adjunct to the system is a monitoring arrangement for permitting monitoring at the remote station of the status of the system at the premises. This monitoring arrangement, illustrated in FIG. 4, includes another deck 42" associated with switch deck 42, and this switch deck 42" includes an OFF contact, an ON contact 102', and a rotor 52".
A potentiometer 1140 is connected between the OFF terminal and the ON terminal 102" of switch deck 42 at the premises (FIG. 1). The slider 1150 of the voltage divider is connected to positive potential. The switch rotor 52 is connected to telephone line 400.
At the remote station, a switch such as NPN transistor 1160 has its emitter connected through a diode 1170 to one side of a voltmeter 1180, the other side of which is connected through a bus 1190 to (telephone) line 410. The emitter of transistor 1160 is also connected through a resistive path 1200 to bus 1190, and the collector is connected by lead 1210 to bus 1220 which is connected both to line 400 and through a resistive path 1230 to bus 1190. The base of transistor 1160 is connected to resistive path 1230.
In operation, the different potentials appearing across the potentiometer 1140 when the switch 52 is ON and when it is OFF, are applied across telephone lines 400 and 410 and through the transistor 1160 and diode 1170 to the meter. This sensing operation does not adversely affect the normal and proper operation of the entire system.
Another modification of the system of the invention illustrated in FIG. 5 includes an adjunct to remote module 420. This modification includes means for providing a remote signal indication by alarm 1030 whenever trouble light 560 is energized and for whatever reason. The circuit is identical to that of FIG. 2 except that the base of SCR 860 and resistor 830 in lead 834 are connected together by lead 1240 to onecontact 1250 of a normally open switch, e.g., a reed switch 1254, the
other contact 1260 of which is connected to lead 730. The switch includes a winding 1263 connected across trouble light 560.
In operation of the circuit of FIG. 5, whenever SCR 570 is fired and trouble light 560 is energized, current flows through winding 1263 to close contacts 1250 and 1260 of switch 1254. This causes SCR 860 to fire and to thereby cause alarm 1030' to operate as described above.
Another adjunct to the system of the invention, illustrated in FIG. 6, is used to permit audio communication between the protected premises and the remote station. This adjunct includes an audio amplifier 1270 having the usual audio or microphone input 1280, power input leads 1290 and 1291 coupled to lines 40 and 50, and output leads 1300 and 1302 connected to lines 400 and 410 of the signalling'system shown in FIG. 2. One section 1310 of a three-part normally open switch 1320 is in each of lines 1300, 1302, and 1291. A winding 1330 is connected across signalling device 80 for operating the switch sections 1310 (A, B, C) and closing them when current flows through alarm 80 and permitting the audio amplifier 1280 to transmit output signals along telephone lines 400 and 410. At the remote station, an audio amplifier 1304 and speaker 1350 are connected across lines 400 and 410.
In operation of this apparatus, when signalling device 80 receives current as the result of an alarm condition detected by module 20 (FIG. 1), winding 1330 is energized and closes switch sections 1310 A, B, and C and permits audio signals, for example, an alarm warning of some kind to be picked up by the microphone 1280 on the premises and transmitted to the remote station and audio amplifier 1340 and speaker 1350 whereby an operator can hear the transmitted audio signals and respond accordingly.
It is noted that audio amplifier 1270 is powered up and transmit only during an alarm condition so that the remote station cannot eavesdrop on the premises during non-alarm periods.
The system of the invention also includes a circuit module 2000 (FIG. 7) for automatically turning off the alarms and sensors of module 20 and resetting the system, in the situation where an alarm condition triggers module 20 and there is no one at the premises to turn off the alarm after due action has been taken.
This circuit module 2000 includes a connection 2005 from the anode of SCR 60 in module 20 through a resistor 2010 and a diode 2020 to the gate G of an SUS switch 2030 which has its cathode K connected through a resistive path 2040 to the base of an NPN transistor 2050 having its collector connected to bus 40 and its emitter connected to bus 50. The collector of the transistor 2050 is also connected to one side of a capacitor 2060, the other side of which is connected through a resistive path to bus 40. A programmable unijunction transistor 2070 is provided having its anode and gate connected across the capacitor 2060 and through suitable resistive paths to bus 40. The cathode of the unijunction transistor is connected to series transistors 2080 and 2090, which form a Darlington circuit, the output of which is coupled to an electromagnetic relay 3000 including a winding 3010 and two normally closed contacts 3020 and 3030, contact 3030 being connected to positive telephone battery potential.
In operation of the circuit of FIG. 7, when an alarm condition is detected in module 20 and SCR 60 fires, ground potential at the anode of SCR 60 is coupled through diode 2020 to the switch 2030 which is turned on. The resultant current flow applies a positive potential to the base of transistor 2050 which turns on and provides a conductive path for charging capacitor 2060. The capacitor is selected and the circuit is designed so that a suitable length of time, for example, ten minutes or so, is required to charge the capacitor 2060. At the end of this time, the capacitor is charged to such a potential that the unijunction transistor 2070 tires, and it in turn fires the two transistors of the Darlington circuit to provide current flow through the winding 3010 and to open the contact elements 3020 and 3030. This momentarily disconnects positive battery potential from the system and thus de-activates the entire system and permits all of the elements thereof to be reset, at which time the contact elements 3020 and 3030 return to their normal closed condition to reconnect positive battery potential to the system. If the alarm condition still remains, it is detected by module 20, and the alarm condition will persist until circuit 2000 operates again to reset the system. This cycle of events will occur until someone at the premises turns off the alarm and corrects the alarm condition.
The system of the invention also includes an electronic key circuit 1103, illustrated in FIG. 8, for automatically signalling the setting of the system on leaving the premises in the evening or the disarming of the system on entering the premises in the morning. With this circuit, no switch is required outside the premises to arm or disarm the system. The circuit of FIG. 8 includes many elements which are equivalent to elements shown in FIG. 1, as will be clear to those skilled in the art. The automatic electronic key circuit includes a three-segment or three-position rotary switch 1110 which may be ganged to switch 42 of FIG. 1. Contact 1110A of switch 1110 is connected by lead 1120 to the negative terminal of battery 1130 (which is equivalent to battery 112 of FIG. 1) and through lead 1140 to a two-position relay 1150. The relay 1150 includes a winding 1160, a movable contactor 1170 and fixed contacts 1180 and 1190. Normally, contactor 1170 is in contact with fixed contact 1190. Contact 1190 of relay 1150 is connected by lead 1200 to contact 1110D of switch 1110, and contact 1180 is connected to lead 1210.
g The winding 1160 has end 1160A connected to lead 1220 and end 1160B connected to lead 1230. A lamp 1240 is connected across winding 1160. Winding end 11608, through lead 1230, is connected to lead 1250 I to the positive terminal of battery 1130. A lead 1260 extends from the positive terminal of battery 1130 and lead 1230 to bus 40 in circuit module 20. End 1160A of winding 1160 is connected bylead 1220 to contact 1270, normally closed to contact 1280, of a relay 1290 having a winding 1300. Lead 1220 is also connected by lead 1223 to contact 1110B of switch 1110. Contact 1280 extends through lead 1310 to a normally closed hand-operated switch 1328, such as a push-button switch, and thence to lead 1210 to contact 1180 of relay 1150.
Winding 1300 of relay 1290 includes end 1300A connected to lead 1310 and end 1300B connected to lead 1320 and to lead 1230 which is coupled to the positive terminal of battery 1130. Lead 1310 from winding 13 1300 is connected to the anode of SCR 1330, the cathode of which is connected to lead 1340'which is connected by lead 1350 back to lead 1310. The cathode of SCR 1330 is also connected both to lead 1360 and through resistor 1370 to its gate. The gate of SCR 1330 is also connected through a lead 1380, diode 1390 (oriented as shown) and a resistor 1400 to lead 1410. I
Contact 1110C of switch 1110 is connected by lead 1430 to a delay switch 1440 having contacts 1450 and 1460 located in a door 1463 of th premises. The contacts are open when the door'is closed and vice versa. Contact 1460 is connected by lead 1470 and resistive path 180 to bus 40 of circuit module 20. Contact 1110D of switch 1110 is connected by lead 1480 to the negative bus of module and to the gate G of SUS switch 120 of module 20 and to lead 1200 to switch contact 1190.
Lead 1470 from lead 40 of circuit 20 and from door switch 1440 is also connected by lead 1500 through diode 1510, oriented as shown,- through resistor 1530 to the base of PNP transistor 1540 which has its emitter connected to lead 1320. The collector of transistor 1540 is connected (1) through resistor 1550 to lead 1560 which is connected to lead 1360 (to SCR 1330) and (2) through resistor1570 and diode 1580, oriented as shown, to the gate of SCR 1590 which has its anode connected to lead 1320 to end 13008 of switch winding 1300. The gate of SCR 1590 is also connected through resistor 1600 and parallel capacitor 1610 to lead 1560. The cathode of SCR 1590 is connected through resistor 1620 to lead 1560 and through lead 1630 to the anode of SCR 1640, the cathode of which is connected through resistor 1650 to lead 1560 and through lead 1410, resistor 1400, and diode 1390 to the gate of SCR I330. The gate of SCR 1640 is connected through resistor 1660 to lead 1560 and through lead 1670 and diode 1680, oriented as shown, and resistor 1690 to lead 1700 which is connected to the lead 1520 from the cathode of diode 1510.
The automatic electronic key circuit 1103 is particularly adapted to operate withthe flasher circuit 32 shown in FIG. 1 although it may be used with other signalling circuits. When used with circuit 32, bus 102 thereof is connected by lead 1703 to the positive terminal of battery 1130 and bus 302 is connected by lead 1705 to the negativeterminal of battery 1130. Lead 282 from the base of transistor T1 is connected to lead 1430 and the contact-1110C of switch. 1110.
Under normal conditions during the day, the premises door 1463 is closed and switch 1440 is open; All circuit elements are inactive, all transistors are nonconducting, the alarm circuit is inactive, current flows through winding 1160, and armature 1170 is held against contact 1180 in relay 1150. When the occupant of the premises opens the door 1463 to leave, the i switch 1440, which is operated by the door, closes.
The operator turns the rotor 1110R of switch 1110 from OFF to ON, from contact 1110A through contact 1110B to contact 1110C. In this case, nothing else happens in switch 1110. As described above, the switch movement through contact 11103 instantaneously couples negative potential to end 1160A of winding 1160, causes current flow through the winding, and causes relay 1150 to move arm 1170 into contact with contact 1180. A circuit is now completed from the negative terminal of battery 1130, through lead 1430, closed switch 1440, leads 1470 and 1500 to apply a negative potential to the base of transistor 1540. Transistor 1540 conducts and generates a positive pulse which is coupled through diode 1580 to the gate of SCR 1590. SCR 1590 conducts and couples positive potential from the battery through lead 1233 and lead 1320 and through lead 1630 to the anode of SCR 1640. SCR 1640 does not conduct because its gate is negative due to the negative potential which is applied to the base of transistor 1540 and which is also coupled through lead 1700, resistor 1690, and diode 1680 to the gate of SCR 1640. In this phase of the operation, flasher circuit 32 is also partially set, as described above, when negative potential is applied to contact 1110B.
Now the door 1463 is closed and switch 1440 is opened and the negative potential which had been coupled through to SCR 1640 is removed. Now positive potential is coupled from the battery 1 130 through lead 1233, lead 1260, bus 40, resistive path 180 to bus 1470, lead 1500, diode 1510, lead 1700, resistor 1690, and diode 1680 to the gate of SCR 1640. SCR 1640 now conducts a positive pulse over lead 1410, resistor 1400, and diode 1390, and the gate of SCR 1330. SCR 1330 conducts and passes current through winding 1300 to open switch 1270. This action cuts off current flow through winding 1160 and releases arm 1170 back to contact terminal 1190. Now negative potential flows over lead 1140 and lead 1200, to lead 1480 and the and arming of the system.
When the occupant returns to the premises in the morning or at any other time and the door 1463 is opened, switch 1440 is closed, and negative potential is coupled through contact 1110C of switch 1110 through leads 1430 and 1470 to turn on SUS 190 and start the delay of module 20 operating. The occupant of the premises then turns switch from on to off, and the circuit is de-energized before the alarm goes off.
It is clear that the various modules described above can all be connected together to provide a unitary alarm system. If desired,however, a suitable alarm system can be provided incorporating fewer than all of these modules.
What is claimed is:
1. A premises protection system comprising a power supply,
an alarm-sensing circuit,
a signalling circuit for indicating the setting of said alarm-sensing circuit,
a multi-position switch having a rotor and a plurality of operating positions including an OFF position, an ON position, and an intermediate position,
a two-position switch,
a two-position relay having an armature, first and second contacts, and an electrical winding, the armature being normally in a first position in which it is in contact with said first contact,
said intermediate contact of said multi-position switch being connected to one side of said power supply and the rotor of said multiposition switch being connected to the other side of said power pp y movement of the rotor of said multi-position switch from said OFF position through said intermediate position to said ON position completing a current flow path through said winding of said relay and causing said armature of said relay to switch from its first position to a second position in which said armature is in contact with said second contact and said power supply is disconnected from said alarmsensing circuit,
operation-of said two-position switch disconnecting said winding of said relay from said power supply and releasing said armature from said second position in which it is in contact with said second contact and causing it to return to its first position in which it is in contact with said first contact whereby said power supply is connected to said alarm-sensing circuit and said signalling circuit is energized to transmit a signal which indicates that power has been connected to said alarm-sensing circuit.
2. The system defined in claim 1 and including in said alarm-sensing circuit first alarm signalling means,
a first electronic circuit module including first bistable switchingmeanshaving two states of operation, in one of which it is unenergized and quiescent and, in the second of which, it senses a first alarm condition and generates a first electrical signal in response thereto, said first electrical signal operating said first alarm signalling means,
a second electronic circuit module including second bistable switching means having two states of operation, in one of which it is unenergized and quiescent and, in the second of which, it senses a second alarm condition and generates a second electrical signal in response thereto, said second electrical signal operating said first alarm signalling means,
a third electronic circuit module coupled to said first and second electronic circuit modules and having input terminals coupled to said first and second circuit modules and having first and second output terminals for indicating which of its two states each of said first and second electronic circuit modules is in, and
a fourth circuit module including second signalling apparatus and coupled to said first and second output terminals,
said output terminals of said third electronic circuit module carrying one set of potentials and energizing one portion of said fourth circuit module when said first and second circuit modules are in an unenergized and quiescent state, said output terminals carrying a second set of potentials and energizing another portion of said fourth circuit module when one or both of said first and second electronic circuit modules is in an alarm-signalling state.
3. The system defined in claim 2 wherein one of said first or second circuit modules includes time delay means for delaying its operation of said first alarm signalling means.
4. The system defined in claim 2 wherein said fourth circuit module is coupled to said third module and said second signalling apparatus includes a first indicator means indicating a normal state for said system when said output signal is not present and said third module is in its first state, and a second indicator means indicating an alarm state when said 16 output signal is present and said third module is in its second state.
5. The system defined in claim 4 wherein, in said fourth module, said first indicator means includes a normal condition indicator and a gate, and said second indicator means includes an alarm condition indicator and a gate,
first power supply means coupled to and applying an AC signal across both said alarm condition indicator and gate, and said normal condition indicator and gate, each said gate preventing said AC signal from turning on its associated indicator, and
a second power supply means coupled through control means to said gates for applying an enabling signal thereto and for operating the same and their associated indicators under control of said control means.
6. The system defined in claim 2 wherein said first and second output terminals of said third circuit module are coupled through a first pair of oppositely oriented diodes to first and second switching devices which are connected so that they turn ON and CF F together in response to the potentials on said first and second output terminals of said third module,
said first switching device being coupled through a first circuit path to a first trouble indicator having a first gate, said second switching device being connected through a second circuit path to a second normal indicator having a second gate, said first and second output terminals also being connected through a second pair of oppositely connected diodes to third and fourth circuit paths, said third path including a switching device connected to a third alarm indicator having a third gate,
said fourth path being coupled to a fourth remote alarm indicator having a fourth gate, and
a signal source providing signals for operating said first, second, and third indicators and coupled to said first, second, and third circuit paths, said paths being open or blocked to said signals depending on the conductive state of said switching devices, and the state of said diodes being determined by the potentials on said first and second output terminals of said third circuit module.
7. The system defined in claim 1 wherein said alarmsensing circuit includes positive and negative buses, and said alarm-sensing circuit in addition is coupled through transmission lines to a remote indicator circuit at a location remote from the protected premises, v
a normally open switch across said transmission lines,
and i v a series-connected transistor switch and lamp'connected between said positive and negative buses whereby closure of said switch turns on said transistor switch and said lamp.
8. The system defined in claim 7 including an auxiliary switch ganged to said three-position switch and including OFF and ON terminals, between which a potentiometer is connected, the slider of said potentiometer being connected to positive potential, and
a circuit connected between said transmission lines at said remote location comprising a transistor switch having a meter in its output circuit, said meter providing one reading when said auxiliary switch is in the OFF state and a second reading when said auxiliary switch'is in the ON state.
9. The system defined in claim 1 wherein said alarmsensing circuit includes an alarm means,
a microphone and a first audio amplifier at said premises, said first audio amplifier having a pair of output lines and a power line, all normally open,
a remote indicating circuit at a remote location coupled'through transmission lines to said first alarmsensing circuit,
means associated with and operated by said alarm means and coupled to said output and power lines to couple said output lines of said first audio amplifier to said transmission lines to transmit sound from said premises along said transmission lines,
a second .audio amplifier and a speaker connected to said transmission lines at said remote location whereby said sounds can be heard at said remote location.
10. The system defined in claim 1 wherein said alarm-sensing circuit includes an alarm means,
a relay connected across said alarm means and having three armatures,
a first audio amplifier having a pair of output lines coupled to but normally not contacting two of said armatures,
a power lead extending from said audio amplifier to said third armature but normally not in contact therewith,
a remote indicating circuit at a remote location coupled through transmission lines to said alarmsensing circuit,
said two of said armatures being connected to said transmission lines whereby, when said armatures close into contact with said two output lines, the output of said audio amplifier can be transmitted along said transmission lines to said remote indicating circuit, and
a second audio amplifier and a speaker connected to said transmission lines at said remote location whereby personnel at said remote location can receive transmissions from said first audio amplifier.
11. The system defined in claim 1 wherein said first alarm-sensing circuit includes an alarm means,
a connection from said alarm means to a semiconductor amplifier means and to a programmable unijunction transistor having a time delay circuit at its input,
the output of said unijunction transistor being connected through a switching circuit to a relay having a normally closed switch means in the power line of said system whereby operation of said alarm means turns on said semiconductor amplifier and charges said time delay circuit which fires said unijunction transistor and said switching circuit to operate said relay and thus to open said power line and disable said alarm-sensing circuit whereupon said relay closes said switch and re-establishes the continuity of said power line.
12. The system defined in claim 2 wherein said first output terminal is coupled to a first pair of oppositely oriented diodes and said second output terminal is coupled to a second pair of oppositely oriented diodes,
said first pair of diodes being coupled through first and second switching devices to first and second circuit paths, the first circuit path including a trouble indicator means and the second circuit path including a normal indicator means,
said second pair of diodes being connected through third and fourth switching devices to third and fourth circuit paths, the third circuit path including a first alarm indicator means and the fourth cir cuit path including a second alarm indicator means, and
a signal source providing signals for operating said first, second, and third indicator means and coupled to said first, second, and third circuit paths, said paths being open or blocked to said signals depending on the conductive state of said first and second pairs of switchingdevices, and the state of said diodes being determined by the potentials on said first and second output terminals of said third circuit module.
13. The system defined in claim 12 wherein said first, second, third and fourth switching devices are semiconductor devices.
14. The system defined in claim 12 wherein said first, second, and third switching devices are transistors having at least three electrodes and said fourth switching device is a three-electrode controlled rectifier.
15. The system defined in claim 12 wherein one diode of said first pair of diodes is connected to any input electrode of each of said first and second switching devices and one diode of said second pair of diodes is connected to an input electrode of each of said third and fourth switching devices.
16. The system defined in claim 12 wherein said fourth circuit path includes a time-delay pulse generating circuit which comprises said fourth switching device and a capacitor, said fourth switching device being rendered conductive to operate said second alarm indicator means when said capacitor is charged by current flowing in said fourth circuit path as the result of an alarm condition sensed by said system.
17. The system defined in claim 12 and including a normally open relay connected across said trouble indicator means and coupled to said fourth switching device whereby, whenever said trouble indicator means turns on, said fourth switching device and said second alarm indicator means are operated.
18. The system defined in claim 6 wherein said first and second switching devices comprise first and second semiconductor devices coupled together and adapted to be ON'or OFF together in response to signals on said first and second output terminals of said third module,
when said first and second switching devices are ON together due to first ones of said signals on said output terminals, said second switching device couples signals from said signal source to said second gate to operate said normal indicator and said first switching device prevents said signals from said signal source from operating said first gate and said first trouble indicator, and when said first and second switching devices are OFF together due to others of said signals at said output terminals of saidv third module, said others of said signals operate said third switching device and said fourth gate and said third and fourth circuit paths are operative and operate the alarm indicators therein.
for fully setting said circuit into operation or for partially setting said circuit, depending on which of the two actions of said switch is employed,
a first switch coupled to said signaling circuit and adapted to be operated by authorized personnel to complete the setting and operation thereof when said circuit has been partially set and authorized personnel leave the premises,
a second switch coupled to and operated by said master switch for partially setting said circuit, said first switch being coupled to and operating said second switch for completing the setting of and operation of said circuit,
said master switch including an OFF contact, an ON contact, and an intermediate contact, said intermediate contact being coupled to and causing operation of said second switch to partially set said signaling circuit,
said second switch including a contactor arm and first and second contacts,
said apparatus further including a power source,
said signaling circuit including a first gate portion and a second portion which can operate a signal system,
turning of said master switch through said intermediate contact serving to momentarily complete a cir cuit path from said power source through said second switch whereby said contactor arm is moved from normal contact with said first contact into contact with said second contact whereby power is coupled to said signaling circuit and said first gate portion thereof is energized but not said second portion thereof,
said first switch being normally closed and being in said circuit path, momentary opening of said first switch de-activating said second switch and moving said contactor from said second contact to said first contact, whereby power is removed from said first portion of said signaling circuit whereby said second portion of said signaling circuit can operate and can energize said signal system.
20. The circuit defined in claim 19 wherein said first gate portion of said signaling circuit includes a capacitor arrangement which charges and holds off said second portion of said signaling circuit,
discharge of said capacitor arrangement when said first switch is operated serving to energize said second portion of said signaling circuit.
21. The circuit defined in claim 19 wherein said first gate portion of said signaling circuit includes a capacitor arrangement which charges and holds off said second portion of said signaling circurt,
discharge of said capacitor arrangement when said first switch is operated serving to energize said second portion of said signaling circuit, and
said second portion of said signaling circuit including a first su b-circuit and a second sub-circuit, said first sub-circuit having a short time constant for operating a remote light-flashing arrangement, said second sub-circuit having a longer time constant for 20 controlling the time duration of the operation of said first sub-circuit.
22. A premises protection system comprising a power supply,
an alarm-sensing circuit,
a signalling circuit for indicating the setting of said alarm-sensing circuit,
a multi-position switch having a rotor and a plurality of operating positions including an OFF position, an ON position, and an intermediate position,
a two-position switch,
a two-position relay having an armature, first and second contacts, and an electrical winding, the armature of said relay being normally in a first position in which it is in contact with said first contact,
said intermediate contact of said multi-position switch being connected to one side of said power supply and the rotor of said three-position switch being connected to the other side of said power pp y,
a door in said premises and a door switch mounted in said door, said switch being open when the door is closed and closed when the door is open,
a first connection from said ON position of said multi-position switch to said door switch,
movement of the rotor of said multi-position switch from said OFF Position through said intermediate position to said ON position completing a current flow path through said winding of said relay and causing said armature of said relay to switch from its first position to its second position in which said armature is in contact with said second contact and said power supply is disconnected from said alarmsensing circuit,
a switching circuit including said two-position switch coupled to and adapted to operate said relay and having a second connection to said first connection through said door switch, said switching circuit including a transistor having its input coupled to said second connection and its output coupled to first and second semiconductor switches, said transistor and said first semiconductor switch being turned on when said multi-position switch is turned ON, subsequent closing of said door and opening of said door switch serving to apply operating potential to said second semiconductor switch to operate said relay and said signalling circuit to signal the arming of said alarm-sensing circuit.
23. A premises protection system including an alarm-sensing circuit for detecting alarm conditions at said premises,
a signaling circuit for indicating the state of said alarm-sensing circuit and whether it has been disabled or enabled by an occupant of the premises,
a first switch which is a multi-position switch and includes an OFF position, an intermediate position, and an ON position,
a door associated with said premises,
a door switch coupled to said door and open when said door is closed and closed when said door is open,
a power supply,
a first relay having an armature, a first contact, a second contact, and a winding,
closed switch to a second relay having a contact, an armature, and a winding,
said armature of said first relay being connected to one side of said power supply,
a connection from said intermediate contact of said multi-position switch through said winding of said first relay to the other side of said power supply,
a circuit loop including a transistor coupled through a diode to a first SCR switch to a second SCR switch through a diode and a third SCR switch to the winding of said second relay,
a connection from said ON contact of said switch through said door switch (1) through a diode to said transistor and (2) through a lead to the alarmsensing circuit,
a connection from a contact of said multi-position switch to said alarm-sensing circuit,
a connection from said intermediate position of said multi-position switch to said winding of said first relay whereby, when the rotor of said multiposition switch is moved from the OFF position through the intermediate position to the ON position, a current flow path is completed from said power supply through said winding of said relay and said armature is moved to said second contact,
a connection from said ON position to said signalling circuit for partially setting the same when said rotor is moved from said OFF position to said ON position and potential is coupled from said power supply to said signalling circuit,
opening of said door causing said door switch to close and couple potential from said power source to said transistor to cause it to conduct and apply operating potential to an electrode of said second SCR switch,
closing of said door causing said door switch to open and apply positive potential to the gate of said second SCR switch which fires and causes said second relay winding to conduct and open and cut off current from the winding of said first relay whereby its armature goes back to said first contact to apply arming potential to said alarm-sensing circuit and to operate said signalling circuit.